Selective oxidation of methane to produce aldehydes and alcohols opens new opportunities for the development and utilization of natural gas resource, and has been gained more and more attention. However, the prior art fails to develop a catalyst which gives an industrially acceptable aldehyde/alcohol yield up to now. The main reason lies in that methane is so inert that elevated temperatures should be involved for activation, at which temperature, not only the non-catalytic gas-phase oxidation reaction is enhance as a competition reaction, but also the selective oxidation product from the catalytic reaction is vulnerable to further oxidation due to its greater reaction activity than methane, and converted into a product with higher oxidation state, like CO, CO2 and H2O. For this reason, how to decrease the activation temperature of methane so as to enhance the selectivity to the aimed product remains one of the critical problems to be solved in this field. Further, the prior art mainly aims at developing a process for producing formaldehyde and methanol by a methane selective oxidation reaction, while few report concerns the technology for producing ethanol or acetaldehyde by a methane selective oxidation reaction.
Therefore, there is still a need for a methane selective oxidizing catalyst, which is especially suitable for co-producing ethanol and acetaldehyde by a methane selective oxidation reaction.